Table 1.

Linear regression analysis was used to investigate the association between CTmax, male FTL₅₀ and Topt and climate across ten Drosophila species (only data from eight species were available for Topt).

Trait	Predictor	Adj. R2	Slope	P	AIC
CTmax	Latitude (°)	0.319	0.084	0.052	27.40
	AMT (°C)	0.081	–0.009	0.217	30.39
	TMAX (°C)	<0.001	–0.014	0.471	31.72
	TWARM (°C)	0.057	–0.016	0.250	30.65
	PANN (mm)	0.301	–0.011	0.058	27.66
	PWET (mm)	0.289	–0.002	0.063	27.82
	TMAX + TWARM	0.269	–	0.139	28.77
	TMAX + PANN	0.366	–	0.084	27.35
	TMAX + PWET	0.390	–	0.074	26.97*
	TWARM + PANN	0.293	–	0.123	28.44
	TWARM + PWET	0.359	–	0.088	27.46
Male FTL50	Latitude (°)	0.278	0.114	0.067	35.10
	AMT (°C)	0.196	–0.017	0.112	36.10
	TMAX (°C)	<0.001	–0.235	0.377	38.42
	TWARM (°C)	0.136	–0.027	0.159	36.83
	PANN (mm)	0.432	–0.002	0.023	32.63
	PWET (mm)	0.524	–0.003	0.011	30.87
	TMAX + TWARM	0.476	–	0.043	32.49
	TMAX + PANN	0.535	–	0.028	31.30
	TMAX + PWET	0.791	–	0.002	23.29*
	TWARM + PANN	0.438	–	0.055	33.18
	TWARM + PWET	0.790	–	0.002	23.36
Topt	Latitude (°)	0.282	0.082	0.101	24.08*
	AMT (°C)	0.028	–0.009	0.315	26.50
	TMAX (°C)	<0.001	–0.016	0.445	27.12
	TWARM (°C)	<0.001	–0.012	0.452	27.15
	PANN (mm)	0.226	–0.001	0.226	25.84
	Pwet (mm)	<0.001	–0.001	0.419	27.02
	TMAX + PANN	0.001	–	0.430	27.27
	TMAX + PWET	<0.001	–	0.739	30.00
	TWARM + PANN	0.105	–	0.327	26.39
	TWARM + PWET	<0.001	–	0.744	29.02

Climatic predictors included latitude (commonly used as a proxy for temperature), annual mean temperature (AMT), maximum temperature of the warmest month (T_MAX), mean temperature of the warmest quarter (T_WARM), annual precipitation (P_ANN) and precipitation of the wettest quarter (P_WET). The association between these traits and the predictor variables T_MAX, T_WARM, P_ANN and P_WET were also compared using a multiple regression approach. Significant P values are highlighted in bold, while the model with the best Akaike Information Criterion (AIC) is highlighted with an asterisk. Source data are provided as a Source Data file.